Gunsmithing for Extreme Range rifles

#1
I need to make changes to get my ELR to additional ranges. It was built up on a integral picatinny. Is there such a thing as a picatinny (top and bottom) rail to put over the integral rail that would be milled for the additional vertical requirement. It would have to be about 10 inches long and add a minimal amount to the existing integral rail. To give me an additional 60 or so MOA.. I suspect there is no easy way to add a piccatinny over an existing pica tinny without seriously increasing the height

I am rebuilding from a McMillan 50 HBR to a Macmillan A5. Enclosed is the current setup.I may have to use a small section of the V barrel block.
 

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Fursniper

Captain, USMM (retired)
Feb 13, 2017
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#2
I would suggest an Era Tac adjustable inclination mount (see website link below). It too will raise your scope higher though, just like a rail on top of your integral rail would (don't know if somebody actually makes a "rail for a rail") so if your A5 doesn't have the adjustable cheek piece option, you can always get one installed. I have not personally used the Era Tac but have seen a couple of threads by Frank (lowlight) where he recommended it. They are not cheap but from what I have heard so far, they work nicely and give you the flexibility of having whatever amount of cant you need. It'd be a good solution for your situation.

Well crap, can't get the link to copy but just Google Era Tac adjustable mount, that'll get you there.....



 
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#3
I already have a large external adjustable scope that has its own required adjustable feet. The adjustable mount Era Tec is an add-on for traditional
normal scopes. When I build the A5 I will still have the integral base of 6 inches or so that is a given and need to find a way to extend it to maybe 10 inches and increase the cant by maybe 60. it need not be adjustable. The problem is taking this increased cant piece and mating it to the integral mount with MINIMUM height added. Thanx for trying though.
 

Fursniper

Captain, USMM (retired)
Feb 13, 2017
2,210
31
48
Arizona
#4
Well, I guess if you can't find an existing solution, you could always have the integral rail milled flat and add a traditional picatinny rail with the cant and the additional length you want to it. There are places that make custom rails. Granted, that's an extreme step to mill off a perfectly good integral rail but it would solve the problem I guess. That is if I understand what you're trying to accomplish.
 

TripleBull

This one goes to 11
Feb 13, 2017
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#8
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Jeffvn

Gunny Sergeant
Apr 26, 2004
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Las Vegas, NV
#9
SPUHR makes a combo base & rings that has 20MOA you can add it to your current base and immediately gain 20MOA. When I did it on my 338LM Improved, I got the lowest ringset they make (knowing mine was sitting on my existing 20 MOA base) and it works fine. I have an adjustable cheek so it didn't give me any fit issues.

Jeffvn
 
#14
I need to make changes to get my ELR to additional ranges. It was built up on a integral picatinny. Is there such a thing as a picatinny (top and bottom) rail to put over the integral rail that would be milled for the additional vertical requirement. It would have to be about 10 inches long and add a minimal amount to the existing integral rail. To give me an additional 60 or so MOA.. I suspect there is no easy way to add a piccatinny over an existing pica tinny without seriously increasing the height

I am rebuilding from a McMillan 50 HBR to a Macmillan A5. Enclosed is the current setup.I may have to use a small section of the V barrel block.
I was under the impression that the SN-9's external mounts provide about 240 MOA, all up. If that is what you have...you want another 60 MOA? Just so you can say you have 300 MOA available? Have you actually run into a situation where 240 MOA (all up) isn't enough? Please tell us more about the motivation for extra MOA. Thanks.
 

steve123

Lt. Colonel
Mar 16, 2008
7,180
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Flagstaff, AZ
#15
My friend had a scope like that. What would happen is when there was a bunch of elevation dialed on the scope bell would bump against the barrel.

In his case it looks like the tube is going to bump against the rail.

That scope probably needs to be mounted a inch higher.
 

jetmd

Sergeant
Jan 17, 2010
530
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Smithville, MO
#16
My friend had a scope like that. What would happen is when there was a bunch of elevation dialed on the scope bell would bump against the barrel.

In his case it looks like the tube is going to bump against the rail.

That scope probably needs to be mounted a inch higher.
Interesting, this must have occurred on an External adjustment scope? What brand of scope was this? Unertl?
 
Mar 17, 2010
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USA
#19
At what range are you able to zero ?
Our goal was to be able to shoot 3400 + without having any movable parts. We decided to use the Vortex 4.5-27x56 Gen II Razors and with the system we are able to use the full potential of the scope. If needed we can easily aim and shoot a 100 yard zero using the hash marks in the scope as a hold under. A 100 yard zero in my 375 is 8 mils under. This in turn also presents the majority of all shots taken in the midship of the turret travel thus giving the shooter the best spectrum of the lens if there is any difference. With these rifles you don't shoot much under 1500 yards anyways in which 1500 yards would be 0.4 mils up (4 tenths) So given the DA of 6000 the cross hair zero would be 1460 yards, but as stated it's easy to hold under and smack a 100 yard to a 600 yard target all day long if needed. We wanted maximum use of a scope/system that has been correctly calibrated and no other moving parts to deal with.


Cheers
oneshot


 
#21
I was under the impression that the SN-9's external mounts provide about 240 MOA, all up. If that is what you have...you want another 60 MOA? Just so you can say you have 300 MOA available? Have you actually run into a situation where 240 MOA (all up) isn't enough? Please tell us more about the motivation for extra MOA. Thanks.
I do have 240 moa of travel. I am watching the recent pissing contests in Ariz, Texas, Montana for long shoot records and want to play, I have been pent up in the East unable to use the power but am retired and can travel. I am rebuilding my 408 Wildcat from a McMillan 50 bench rest to an A-5 Super Mag and am anxiously awaiting to see what maximum distance they can throw a .408 still spinning and behaving in flight, Once I have that, I would rather take care of that with MOAs necessary than to have to deal with it in ANOTHER rebuild. The construction will be quite different because the big benchrest stick has a V block. I don't think a barrel block is workable for my new stock which leaves me with an awful lot of barrel for the action to take. May have to trim down the 1.35 inch barrel for starters. Also worried about harmonics so welcome input from those building ELR big bores.
 
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